DescriptionRitchey Logic-E Cartridge Press Fit Upper Headset – ZS44/28.6. Ritchey Logic-E headset is designed to work with Shimano STEPS or Di2 routing the cable through the frame without the need to modify fork or frame. TECH SPECSColorBlackS.H.I.S UpperZS44S.H.I.S. Stem Clamp Diameter28.6 Threadless
